METHOD AND SYSTEM FOR ADAPTIVE CONTINUOUSLY VARIABLE TRANSMISSION GEAR RATIO CONTROL

• US 20110183810A1
• Filed: 01/27/2010
• Published: 07/28/2011
• Est. Priority Date: 01/27/2010
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Motor Engineering & Manufacturing North America Incorporated (Toyota Motor Corporation)
• Inventors: Choby, Jordan
• Granted Patent: US 8,585,551 B2
• Time in Patent Office: Days
• US Class Current: 477/120
• CPC Class Codes: F16H 59/48 Inputs being a function of acceleration
• CPC Class Codes: F16H 61/66 specially adapted for continuously variable gearings control of exclusively fluid gearing F16H61/38

Abstract

An automobile comprising a continuously variable transmission (“CVT”) system including an acceleration input device, a CVT, and a processor. The acceleration input device generates acceleration input data indicating an amount of change in the acceleration input device, and a rate of change in the acceleration input device. The CVT includes a power source and a transmission output system. The power source operates at a transmission input speed, while the transmission output system operates at a transmission output speed. The transmission input speed over the transmission output speed comprises a gear ratio. The processor analyzes the acceleration input data to determine a target gear ratio. The processor can instruct the CVT to change the gear ratio to the target gear ratio at a rate corresponding to the rate of change in the acceleration input device.

Claims

1. A continuously variable transmission system comprising:

a continuously variable transmission operating at a gear ratio;

an acceleration input device detecting acceleration input data; and

a processor connected to the continuously variable transmission and the acceleration input device, the processor detecting a rate of change in the acceleration input data and changing the gear ratio based on the rate of change in the acceleration input data.

2. The system of claim 1 wherein the processor determines a target gear ratio based on the acceleration input data, and changes the gear ratio to match the target gear ratio.

3. The system of claim 2 wherein the processor changes the gear ratio at a rate based on the rate of change in the acceleration input data.

4. The system of claim 2 wherein the continuously variable transmission includes

a power source operating at a transmission input speed;

and

a transmission output system operating at a transmission output speed, wherein the transmission input speed over the transmission output speed comprise the gear ratio.

5. The system of claim 4 wherein the processor increases the transmission input speed to increase the gear ratio.

6. The system of claim 5 wherein the processor increases the transmission input speed at a rate based on the rate of increase in the acceleration input data.

7. The system of claim 4 wherein the processor increases the transmission input speed at a first rate based on a first rate of increase in the acceleration input data, and increases the transmission input speed at a second rate based on a second rate of increase in the acceleration input data.

8. The system of claim 7 wherein the first rate of increase in the transmission input speed is greater than the second rate of increase in the transmission input speed when the first rate of increase in the acceleration input data is greater than the second rate of increase in the acceleration input data.

9. An automobile comprising:

a power source operating at a transmission input speed;

a transmission output system operating at a transmission output speed, wherein the transmission input speed over the transmission output speed comprise the gear ratio;

an acceleration input device detecting acceleration input data; and

a processor connected to the power source, the transmission output system, and the acceleration input device, the processor determining a target gear ratio based on the acceleration input data, detecting a rate of change in the acceleration input data, and changing the gear ratio to match the target gear ratio based on the rate of change in the acceleration input data.

10. The automobile of claim 9 wherein the processor changes the gear ratio at a rate based on the rate of change in the acceleration input data.

11. The automobile of claim 9 wherein the processor increases the transmission input speed to increase the gear ratio.

12. The automobile of claim 11 wherein the processor increases the transmission input speed at a rate based on the rate of increase in the acceleration input data.

13. The automobile of claim 11 wherein the processor increases the transmission input speed at a first rate based on a first rate of increase in the acceleration input data, and increases the transmission input speed at a second rate based on a second rate of increase in the acceleration input data.

14. The automobile of claim 13 wherein the first rate of increase in the transmission input speed is greater than the second rate of increase in the transmission input speed when the first rate of increase in the acceleration input data is greater than the second rate of increase in the acceleration input data.

15. A method of varying a gear ratio of a continuously variable transmission system comprising:

operating a continuously variable transmission at a gear ratio;

detecting acceleration input data;

detecting a change in the acceleration input data; and

changing the gear ratio at a rate based on the rate of change in the acceleration input data.

16. The method of claim 15 further comprising

determining a target gear ratio based on the acceleration input data;

and

changing the gear ratio to match the target gear ratio.

17. The method of claim 16 further comprising increasing the gear ratio at a rate based on the rate of increase in the acceleration input data.

18. The method of claim 16 wherein the step of operating the continuously variable transmission at the gear ratio includes:

operating a power source at a transmission input speed; and

operating a transmission output system at a transmission output speed, wherein the transmission input speed over the transmission output speed comprise the gear ratio.

19. The method of claim 16 further comprising increasing the engine speed at a rate based on the rate of increase in the acceleration input data.

20. The method of claim 16 further comprising:

increasing the engine speed at a first rate based on a first rate of increase in the acceleration input data; and

increases the engine speed at a second rate based on a second rate of increase in the acceleration input data,

wherein the first rate of increase in the engine speed is greater than the second rate of increase in the engine speed when the first rate of increase in the acceleration input data is greater than the second rate of increase in the acceleration input data.